<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<style>
  .container{
    position: relative;
  }
  .left{
    position: absolute;
    left: 0;
    top: 0;
    width: 200px;
    height: 200px;
    background: salmon;
  }
  .right {
    position: absolute;
    right: 0;
    top: 0;
    width: 200px;
    height: 200px;
    background: salmon;
  }
  .center{
    margin: 0 210px;
    height: 200px;
    background: red;
  }
</style>
<body>
  <div class="container">
    <div class="left">左边</div>
    <div class="center">zhongian</div>
    <div class="right">右边</div>
  </div>
</body>
</html>